Schistosomiasis, Soil-Transmitted Helminthiasis, and Sociodemographic Factors Influence Quality of Life of Adults in Côte d'Ivoire

Background: Burden of disease estimates are widely used for priority setting in public health and disability-adjusted life years are a powerful “currency” nowadays. However, disability weights, which capture the disability incurred by a typical patient of a certain condition, are fundamental to such burden calculation and their determination remains a widely debated issue. Methodology: A cross-sectional epidemiological survey was conducted in the recently established Taabo health demographic surveillance system (HDSS) in south-central Côte d'Ivoire, to provide new, population-based evidence on the disability caused by schistosomiasis and soil-transmitted helminthiasis. Parasitological results from stool, urine, and blood examinations were juxtaposed to quality of life (QoL) questionnaire results from 187 adults. A multivariable linear regression model with stepwise backward elimination was used to identify significant associations, considering also sociodemographic characteristics obtained from the Taabo HDSS database. Principal Findings: Prevalences for hookworm, Plasmodium spp., Trichuris trichiura, Schistosoma haematobium and Schistosoma mansoni were 39.0%, 18.2%, 2.7%, 2.1% and 2.1%, respectively. S. mansoni and T. trichiura infections of any intensity reduced the participants' self-rated QoL by 16 points (95% confidence interval (CI): 4–29 points) and 13 points (95% CI: 1–24 points), respectively, on a scale from 0 (worst QoL) to 100 points (best QoL). The only other statistically significant effect was a 1-point (95% CI: 0.1–2 points) increase on the QoL scale per one unit increase in a calculated wealth index. Conclusions/Significance: We found consistent and significant results on the negative effects of schistosomiasis and soil-transmitted helminthiasis on adults' self-rated QoL, also when taking sociodemographic characteristics into account. Our results warrant further investigation on the disability incurred by helmintic infections and the usefulness of generic QoL questionnaires in this endeavor. Author Summary: In public health, "burden" estimates should capture the human suffering caused by certain health states, and the estimates are often used for priority setting. However, such "burden" estimates need to assess not only the number of affected people by certain conditions, but also the disability incurred by the average patient, and the determination of the degree of disability remains a widely debated issue. In order to provide new, population-based evidence on the disability caused by infections with parasitic worms, we administered a quality of life (QoL) questionnaire to 187 adults in rural Côte d'Ivoire and concurrently examined them for parasitic worm infections. We also considered sociodemographic characteristics in our analysis. In comparison with their non-infected counterparts, infected people reported a 13–16 points lower QoL on a scale from 0 (worst QoL) to 100 points (best QoL). At the same time, a one unit increase in a calculated wealth index revealed a 1-point increase in the participants' QoL. The results are consistent and warrant further investigation on the disability induced by parasitic worm infections and the usefulness of QoL questionnaires in this endeavor.